&ACCESS RVP
&REL 1
&PARAM TEMPLATE = C:\KRC\Roboter\Template\vorgabe
&PARAM EDITMASK = *
DEF state_machine()
; ================================================================
; Multi-State Coordination Pattern
; ================================================================
; Demonstrates a state machine for complex Python-KRL workflows.
; Uses both I/O signals and Tech variables for robust coordination.
;
; State Definitions:
;   State 0: IDLE - Waiting to start
;   State 1: CALIBRATING - Python performing calibration
;   State 2: READY - Calibration complete, ready for motion
;   State 3: EXECUTING - Robot executing motion task
;   State 4: COMPLETE - Task finished
;   State 9: ERROR - Error condition
;
; I/O Mapping:
;   $OUT[1]: State signal to Python (pulse indicates state change)
;   $IN[1]:  Python acknowledgement
;   $IN[2]:  Python error signal
;
; Tech Variable Mapping:
;   Tech.T[11]: Current state (KRL → Python)
;   Tech.C[11]: Python command (0=continue, 1=pause, 2=abort)
;   Tech.C[12-14]: Calibration offset (X, Y, Z)
;
; Python Code Example:
;   api = RSIAPI('RSI_EthernetConfig.xml')
;   api.start()
;
;   # Monitor state transitions
;   while True:
;       state = api.krl.read_param('T11')
;
;       if state == 1:  # CALIBRATING
;           print("Performing calibration...")
;           # Calibration logic here
;           offset_x = 5.0
;           offset_y = -2.0
;           offset_z = 0.5
;
;           # Write calibration results
;           api.krl.write_param('C12', offset_x)
;           api.krl.write_param('C13', offset_y)
;           api.krl.write_param('C14', offset_z)
;
;           # Acknowledge state completion
;           api.krl.signal_complete(1)
;
;       elif state == 3:  # EXECUTING
;           print("Robot executing motion...")
;           # Monitor execution, send corrections if needed
;           api.motion.update_cartesian(X=offset_x, Y=offset_y)
;
;       elif state == 4:  # COMPLETE
;           print("Task complete!")
;           break
;
;       elif state == 9:  # ERROR
;           print("Error detected, aborting!")
;           break
;
;       time.sleep(0.1)
;
;   api.stop()
; ================================================================

  ; Variable declarations
  INT current_state, python_cmd
  REAL offset_x, offset_y, offset_z
  E6POS target_pos
  BOOL ack_received
  INT timeout_counter

  BAS(#INITMOV, 0)

  ; Initialize state machine
  current_state = 0  ; IDLE
  $TECH.T[11] = current_state

  ; ============================================================
  ; STATE 0: IDLE
  ; ============================================================
  current_state = 0
  $TECH.T[11] = current_state
  WAIT SEC 1.0

  ; ============================================================
  ; STATE 1: CALIBRATING
  ; ============================================================
  current_state = 1
  $TECH.T[11] = current_state

  ; Signal Python to start calibration
  $OUT[1] = TRUE
  WAIT SEC 0.1
  $OUT[1] = FALSE

  ; Wait for Python calibration completion
  ack_received = FALSE
  timeout_counter = 0

  WHILE (ack_received == FALSE) AND (timeout_counter < 200)
    ; Check for error signal
    IF $IN[2] == TRUE THEN
      current_state = 9  ; ERROR
      $TECH.T[11] = current_state
      HALT
    ENDIF

    ; Check for completion
    IF $IN[1] == TRUE THEN
      ack_received = TRUE
    ELSE
      WAIT SEC 0.1
      timeout_counter = timeout_counter + 1
    ENDIF
  ENDWHILE

  IF ack_received == FALSE THEN
    ; Timeout error
    current_state = 9
    $TECH.T[11] = current_state
    HALT
  ENDIF

  ; ============================================================
  ; STATE 2: READY
  ; ============================================================
  ; Read calibration offsets from Python
  offset_x = $TECH.C[12]
  offset_y = $TECH.C[13]
  offset_z = $TECH.C[14]

  current_state = 2
  $TECH.T[11] = current_state

  ; Signal ready
  $OUT[1] = TRUE
  WAIT SEC 0.1
  $OUT[1] = FALSE
  WAIT SEC 0.5

  ; ============================================================
  ; STATE 3: EXECUTING
  ; ============================================================
  current_state = 3
  $TECH.T[11] = current_state

  ; Calculate target with calibration offset
  target_pos = $POS_ACT
  target_pos.X = target_pos.X + offset_x
  target_pos.Y = target_pos.Y + offset_y
  target_pos.Z = target_pos.Z + offset_z

  ; Execute motion (Python can send RSI corrections during this)
  LIN target_pos Vel=0.3 m/s CPDAT1 Tool[1] Base[0]

  ; Check for pause/abort commands
  python_cmd = $TECH.C[11]
  IF python_cmd == 2 THEN
    ; Abort requested
    current_state = 9
    $TECH.T[11] = current_state
    HALT
  ENDIF

  ; ============================================================
  ; STATE 4: COMPLETE
  ; ============================================================
  current_state = 4
  $TECH.T[11] = current_state

  ; Signal completion
  $OUT[1] = TRUE
  WAIT SEC 0.2
  $OUT[1] = FALSE

  ; Return to home
  PTP HOME Vel=100 % DEFAULT

  ; Final state update
  current_state = 0  ; Back to IDLE
  $TECH.T[11] = current_state

END